Installation of, a hub/bearing assembly for an automotive vehicle

ABSTRACT

A tool facilitates the installation of a hub/bearing assembly on a CV joint during the assembly of an automotive vehicle. The hub/bearing assembly has a housing, a hub provided with a spindle that projects into the housing, and a bearing between the spindle and housing to enable the hub to rotate in the housing. The spindle contains an internal spline which mates with an external spline located on a half-shaft of the CV joint, when the hub/bearing assembly is fitted to the CV joint, but the universal movement of the CV joint makes fitting difficult in the absence of the tool. The tool has a sleeve which fits into the spline of the hub spindle and over a reduced end that projects beyond the spline on the half-shaft. It aligns the two splines so that the hub is simply pushed off the sleeve and over the spline of the half-shaft.

RELATED APPLICATIONS

This application derives priority from International ApplicationPCT/US02/06807, filed Mar. 5, 2002, and published under InternationalPublication No. WO 02/070285 A1, and from U.S. Provisional Application60/273,748, filed Mar. 6, 2001.

TECHNICAL FIELD

This invention relates in general to the assembly of automotive vehiclesand, more particularly, to the installation of a hub/bearing assembly onan end shaft with splines on the hub/bearing assembly and end shaftengaged.

BACKGROUND ART

The manufacturers of automotive vehicles rely more and more on packagedcomponents for the vehicles that they assemble. Whereas before, certainparts were installed separately along an assembly line, now many ofthese same parts are incorporated into components which are assembledelsewhere and installed on vehicles in considerably less time and withgreater ease than were the individual parts. The hub assemblies by whichthe road wheels of a vehicle are attached to the suspension system ofthe vehicle provide a good example.

Not long ago, automotive manufacturers, when assembling a vehicle, wouldinstall a spindle as part of the front suspension system of a vehicle,then place an inboard bearing, a hub and an outboard bearing in thatorder around the spindle, followed by a nut threaded over the spindleand tightened against the outboard bearing just enough to give the twobearings the correct setting. Now a parts supplier furnishes a hubfitted to a housing with bearings located between the two and adjustedto the proper setting, that is to say, the parts supplier provides apreassembled hub/bearing assembly. The automotive manufacturer bolts thehousing of the hub/bearing assembly to a suspension system component,and later attaches a brake disk and wheel to the hub.

Drive shafts complicate the procedure, and many vehicles have transverseshafts coupled to their front wheels, whether they be front wheel drivevehicles or four wheel drive vehicles. In this regard, the typicaltransverse shaft leads out to a constant velocity (CV) joint having anenlarged body or shell and a half-shaft projecting outwardly from theshell where it has a spline followed by a reduced end that is threaded.The spline mates with a corresponding spline in the hub of thehub/bearing assembly, while the thread on the reduced end is engagedwith a nut that attaches the CV joint to the hub.

But the CV joint together with the transverse shaft to which it iscoupled are quite heavy, weighing up to 50 lbs., and the hub/bearingassembly is heavy as well, making it difficult for an assembly lineworker to manipulate and align the spline of the hub with the spline onthe half-shaft. To be sure, the threaded end of the half-shaft fitseasily into the larger splined bore of the hub, but does not align thetwo splines. The differences in diameter between the threaded end andthe spline on the half-shaft together with the multiple degrees offreedom accorded to the half-shaft by the CV joint make it difficult andtime consuming to bring the spline on the half-shaft into axialalignment with the spline in the hub—and, of course, the two splinescannot be engaged until they are so aligned.

SUMMARY OF THE INVENTION

The present invention resides in the combination of a tool, ahub/bearing assembly having a splined hub into which the tool fits, andan half-shaft having an external spline and a reduced end over which thetool fits. The tool places the two splines in axial alignment so thatthe hub/bearing assembly may be advanced over the half-shaft with thesplines engaged. The tool is then withdrawn from the half-shaft. Theinvention also resides in the process of installing the hub/bearingassembly on the end shaft using the tool to align the splines.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a longitudinal view showing a hub/bearing assembly and asplined half-shaft engaged with the hub of the hub/bearing assembly;

FIG. 2 is perspective view of the half-shaft and the hub of thehub/bearing assembly maintained in axial alignment with the tool of thepresent invention;

FIG. 3 is a perspective view of the hub/bearing assembly as its hub ismoved off the tool and onto the aligned spline of the half-shaft; and

FIG. 4 is a perspective view of the hub/bearing assembly in its finalposition on the half-shaft and the tool withdrawn from it and from thehalf-shaft.

Corresponding reference characters indicate corresponding partsthroughout the several views of the drawings.

BEST MODE FOR CARRYING OUT THE INVENTION

Referring now to the drawings (FIG. 1), an automotive vehicle has asuspension system component A, which may be a steering knuckle, to whicha hub/bearing assembly B is attached. Actually, the suspension systemcomponent A has a circular opening 2, whereas the hub/bearing assembly Bincludes a housing 4 which fits into the opening 2 of the suspensionsystem component A to which it is bolted. The hub/bearing assembly Balso includes a hub 6 which is located in and beyond the housing 4 and abearing 8 that is located between housing 4 and the hub 6 to enable thehub 6 to rotate in the housing 4 about an axis X. The hub 6 has a brakedisk C and a road wheel D attached to it. Thus, the hub/bearing assemblyB couples the road wheel D to the suspension system component A suchthat the wheel D rotates relative to the component A about the axis X.The hub 6 of the hub/bearing assembly B is driven by a transverse shaftE which is coupled to it through a universal joint such as a constantvelocity (CV) joint F. During the assembly of the vehicle, thehub/bearing assembly B is fitted to the CV joint F with the aid of analignment tool T (FIGS. 2-4).

Considering the hub/bearing assembly B in more detail (FIG. 1), itshousing 4 possesses a generally cylindrical configuration, but has amultilobed flange 10, such as a triangular or rectangular flange,located intermediate its ends. The portion of the housing 4 on theinboard side of the flange 10 fits into the circular opening 2 in thesuspension system component A, bringing the back face of the flange 10against the suspension system component A. The housing 4 is attached tothe suspension system component A with bolts 12 which pass through thelatter from its back face and thread into the former. Internally, thehousing 4 has two tapered raceways 14 which are presented inwardlytoward the axis X. The raceways 14 taper downwardly toward themid-region of the housing 4 and form part of the bearing 8.

The hub 6 has a spindle 20 which fits into the housing 4 and a hubflange 22 which is attached to the spindle 20 beyond the outboard end ofthe housing 4. Externally, the spindle 20 has a tapered raceway 24 thatleads up to a rib 26 located immediately inboard from the hub flange 22.The raceway 24 faces outwardly toward the outboard of the two raceways14 in the housing 4 and is inclined in the same direction. Like theraceway 14, the raceway 24 forms part of the bearing 8. At the oppositeend of the raceway 24, the spindle 20 has a cylindrical bearing seat 28and a formed end 30 to which the seat 28 leads. Internally, the spindle20 has a smooth bore 32 which leads up to an internal spline 34 oflesser diameter. The bore 32 opens out of the formed end 30 at a beveledsurface 35, whereas the spline 34 extends through the spindle 20 andinto the hub flange 22 out of which it opens.

The hub flange 22 has a wheel pilot 36 which projects from its outboardface and a flat seat 38 which surrounds the end of the spline 34 withinthe confines of the wheel pilot 36, Both the hub flange 22 and the flatseat 38 lie perpendicular to the axis X. Finally, the hub flange 22carries lug bolts 40 over which lug nuts 42 are threaded to secure thebrake disk C and wheel D to the hub 6.

In addition to the two raceways 14 in the housing 4 and the raceway 24on the spindle 20 of the hub 6, the bearing 8 includes a separate innerrace in the form of a cone 50 that fits over the bearing seat 28 with aninterference fit and has a tapered raceway 52 that is presentedoutwardly toward the inboard raceway 14 in the housing 4, yet tapersdownwardly in the same direction as that raceway 14. The cone 50 alsohas a thrust rib 54 located at the large end of its raceway 52.

The bearing 8 also includes rolling elements in the form of taperedrollers 58 which are organized into two rows, one an outboard rowbetween the outboard raceway 14 in the housing 4 and the raceway 24 onthe spindle 20, and the other an inboard row between the inboard raceway14 in the housing 4 and the raceway 52 on the cone 50. The tapered OD ofthe rollers 58 in the outboard row contact the raceways 14 and 24between which they are located, whereas the large end faces of thoserollers 58 are against the rib 26. Indeed, the rib 26 prevents therollers 58 of the outboard row from being expelled from the spacebetween the raceways 14 and 24. The tapered OD of the rollers 58 in theinboard row contact the inboard raceway 14 of the housing 4 and theraceway 52 of the cone 50, whereas their large end faces bear againstthe thrust rib 54 the cone 50. The thrust rib 54 prevents the rollers 58of the inboard row from being expelled. Finally, the bearing 8 includesa cage 60 for each row of rollers 58 to maintain the proper spacingbetween the rollers 58 in each row.

The rollers 58 in each row are in apex, meaning the conical envelopesdefined by the tapered OD of the rollers 58 in each row have theirapexes at a common point along the axis X. Moreover, the bearing 8 isset to a condition of slight pre-load, so that no internal clearancesexist within it, and no free motion, either axially or radially, occursbetween the hub 6 and housing 4.

The formed end 30 turns outwardly behind the cone 50 and retains it onthe spindle 20. Initially, the spindle 20 at its inboard end is straightto enable the cone 50 to fit over it, but once the outboard row ofrollers 58 is in place along with the housing 4 and the cone 50 alongwith the inboard row of rollers 58 are fitted over the bearing seat 28,the straight end of the spindle 20 is turned outwardly. PCT applicationGB 98/01823 (International Publication No. WO 98/58762) discloses arotary forming process for upsetting the initially extended end of thespindle 20 and converting that end into the integral formed end 30.

The transverse shaft E is coupled to the CV joint F which in turn iscoupled to the hub 6 of the hub/bearing assembly B. The CV joint Fenables torque that is applied to the shaft E to be transferred to thehub 6 and the wheel D even though the axis of the shaft E may not alignwith the axis X of the hub 6. The CV joint F includes a shell or body 66and an end shaft, more commonly referred to as a half-shaft 68, whichprojects from the body 66 at a shoulder 70. The half-shaft 68 has anexternal spline 72 which leads away from the shoulder 70 and isconfigured to mate with the internal spline 34 of the spindle 20. Thehalf-shaft 68 also has a reduced end 74 which leads away from the spline72 at a lesser diameter, thus providing a shoulder 76 on the shaft 68.The reduced end 74 is provided with threads 78. The half-shaft 68projects through the bore 32 and spline 34 of the hub 6, with itsexternal spline 72 engaged with the internal spline 34 of the hub 6. Theformed end 30 on the hub 6 bears against the shoulder 70 on the body 66of the CV joint F, whereas the reduced end 74 of the half-shaft 68projects out of the spline 34 and beyond the flat seat 38 on the hub 6.Indeed, the threads 78 are exposed at the flat seat 38 that is withinthe wheel pilot 36 on the hub flange 22. The CV joint F is securedfirmly to the hub 6 of the hub/bearing assembly B with a nut 80 thatengages the threads 78 on the reduced end 74 of the half-shaft 68 andbears against a washer 82 that in turn bears against the flat seat 38 onthe hub 6. In effect, the hub 6 is captured between the shoulder 70 andthe nut 80.

An automotive vehicle, while undergoing assembly, advances along anassembly line with its transverse shaft E extending laterally from adifferential or transaxle and the CV joint F coupled to the end of theshaft E. Moreover, the suspension system component A, which is usually asteering knuckle, is connected to a lower control arm (not shown) sothat it can swing upwardly to a generally upright position on thecontrol arm. The hub/bearing assembly B is attached to the suspensionsystem component A, the back portion of its cylindrical housing 4 beingreceived in the circular opening 2 in the component A and its flange 10being secured firmly against the component A with the bolts 12 whichpass through the component A from its backside and thread into the lobesof the flange 10. In this condition the vehicle approaches the stationat which the hub 6 of the hub/bearing assembly B is fitted to thehalf-shaft 68 of the CV joint F.

Heretofore, the assembly line worker had to, with one hand, lift the CVjoint and the transverse shaft E to which it is attached and, with theother hand, lift the united suspension system component A andhub/bearing assembly B, and then manipulate them in an effort to insertthe spline 72 on the half-shaft 68 of the CV joint F into the spline 34in the spindle 20 of the hub 6 for the hub/bearing assembly B. While inthis procedure the end portion 74 of the half-shaft 68 fits easily intothe bore 32 that leads up to the spline 34 in the hub 6, the two splines34 and 72 rarely align. The half-shaft 68, owing to the universalmovement accorded by the CV joint F, can assume numerous angularorientations. This makes it difficult to align the two splines 34 and 72and fit the hub 6 over the half-shaft 68.

The alignment tool T enables the hub/bearing assembly B to be fitted tothe CV joint F with substantially less effort and in considerably lesstime. The tool T includes (FIGS. 2-3) a cylindrical sleeve 90 and aflange 92 at one end of the sleeve 90. Through both passes a cylindricalbore 94 which opens out of the end remote from the flange 92 at achamfer 96. The external diameter of the sleeve 90 is designed to haveslight clearance when inserted into the minor diameter of the internalspline 34 in the hub 6. At this diameter, the sleeve 90 will slideeasily into the spline 34 of the hub 6, until the flange 92 on the toolT comes against the seat 38 at the outboard end of the spline 34 (FIG.2). When the tool T is so positioned, the opposite end of its sleeve 90lies within the formed end of 30 of the spindle 20 for the hub 6. Thediameter of the bore 94 is slightly larger than the diameter of thereduced end 74 on the half-shaft 68, which is enough to enable thesleeve 90 to slide easily over the reduced end 74 of the half-shaft 68on the CV joint F. The tool T is preferably made from a durablematerial, yet a material that is not as hard as the steel of the CVjoint F and the hub 6, so that it will not mar the threads 78 on thehalf-shaft 68 or the spline 34 in the hub 6. A rigid polymer or aluminumwill suffice.

The assembly line worker responsible for installation of the hub/bearingassembly B on the CV joint F fits the tool T into the hub 6 of thehub/bearing assembly B, inserting the sleeve 90 of the tool T into thespline 34 of the hub 6 from the outboard end and advancing the sleeve 90through the spline 34 and into the enlarged bore 32 until the flange 92on the tool T comes against the flat seat 38 (FIG. 2). With the tool Tso disposed, the chamfer 96 at the opposite end of the sleeve 90 lieswithin the formed end 30 at the inboard end of the hub spindle 20. Asthe vehicle on the assembly line approaches with the half-shaft 68 ofits CV joint F projecting generally laterally and the housing 4 of thehub/bearing assembly B attached to the suspension system component A,the assembly line worker grasps the CV joint F with one hand and thebearing assembly B with the other and inserts the reduced end 74 on thehalf-shaft 68 of the CV-joint F into the bore 94 in the sleeve 90 of thetool T, which in turn, is in the hub 6 of the hub/bearing assembly B.The chamfer 96 at the end of the bore 94 guides the reduced end 74 intothe sleeve 90 with only minimal manipulation. The sleeve 90 is advancedover the reduced end 74, indeed, until its chamfered end bears againstthe shoulder 76 at the end of the external spline 72 on the half-shaft68 (FIG. 2). This brings the spline 72 on the half-shaft 68 and thespline 34 in the spindle 20 of the hub 6 into axial alignment.Thereupon, the bearing assembly B is rotated on bearing 8 until the twosplines 34 and 72 will mate, whereupon the hub/bearing assembly B isadvanced onto the half shaft 68 of the CV joint F (FIG. 3). The internalspline 34 in the hub 6 passes over the external spline 72 on thehalf-shaft 68 until the formed end 30 on the spindle 20 of the hub 6approaches the shoulder 70 on the body 66 of the CV joint F. As the hub6 slides over the spline 72 on the half-shaft 68, the sleeve 90 of thetool T remains on the reduced end 74 of the half-shaft 68, inasmuch asthe chamfered end 96 of the sleeve 90 bears against the shoulder 76between the reduced end 74 and spline 72. Thus, the spline 34 of the hub6 slides off the sleeve 90, leaving the flange 92 exposed where it maybe easily grasped (FIG. 3). When the formed end 30 on the spindle 20 ofthe hub 6 reaches the shoulder 70 on the CV joint F, the worker graspsthe tool T and withdraws it from the hub 6, setting it aside for useinstalling another hub/bearing assembly B (FIG. 4).

At this juncture, the worker places the washer 82 over the exposedportion of the reduced end 74 and then engages the threads 78 with thenut 80. The worker tightens the nut 80 down tightly against the washer82, so that the hub 6 is captured firmly between the shoulder 70 of theCV joint F and the nut 80 (FIG. 1).

Variations are, of course, possible. Perhaps the broadest variation isthat the invention is equally effective for other traditional drivesystems, such as traditional universal joint applications. For example,the cone 50 may be retained with a nut or ring instead of the integrallyformed end 30. The bearing 6 may have two separate cones 50 instead ofone. Also the bearing 6 may have rolling elements of otherconfigurations, for example, balls as in an angular contact ballbearing. The suspension system component A may be supported on rearwheels, in which event it need not pivot about an upright axis as does asteering knuckle.

1. In combination with an automotive vehicle that is partially assembledand includes an end shaft that has an external spline and a reduced endof lesser diameter that is located beyond the spline and extends to theend of the shaft, and that further includes a hub/bearing assemblyhaving a housing, a hub having a spindle that projects into the housingand has an internal spline that is configured to mate with the externalspline on the shaft, and a bearing located between the spindle of thehub and the housing to enable the hub to rotate; an assembly tool forfacilitating installation of the hub spindle over the end shaft, saidtool comprising: a sleeve located within the spline of the hub andaround the reduced end portion of the end shaft and axially aligning thespline of the hub with the spline of the shaft.
 2. The combinationaccording to claim 1 and further comprising a transverse shaft on thevehicle and a universal joint connected to the transverse shaft; andwherein the end shaft forms part of the universal joint.
 3. Thecombination according to claim 2 wherein the universal joint has a bodythat is wider than the end shaft, and the body has a shoulder from whichthe end shaft projects, and the end shaft is fixed in position withrespect to the body.
 4. The combination according to claim 3 and furthercomprising a suspension system component having an opening in which thehousing of the hub/bearing assembly is received; and wherein the body ofthe universal joint lies generally behind the opening.
 5. Thecombination according to claim 4 wherein the hub has a flange which isattached to one end of the spindle and the flange lies beyond thehousing.
 6. The combination according to claim 1 wherein the toolextends beyond the internal spline of the hub spindle and out of the hubto a location where it can be grasped.
 7. The combination according toclaim 1 wherein the tool has a flange at one end of the sleeve, and theflange is located beyond the spline in the hub spindle where it can begrasped.
 8. A process for installing a hub/bearing assembly on partiallyassembled automotive vehicle that includes a transverse shaft and auniversal joint coupled to the end of the transverse shaft and has abody and a half-shaft projecting from the body, the half-shaft having anexternal spline and a reduced end located beyond the external spline andbeing of a lesser diameter than the spline, the hub/bearing assemblyincluding a housing, a hub having a spindle which is located within thehousing and has an internal spline that is configured to mate with theexternal spline on the half-shaft, and a bearing located between thespindle and the housing to enable the hub to rotate on the housing; saidprocess comprising: placing the hub/bearing assembly around thehalf-shaft of the universal joint such that end portion of half-shaft isreceived in the spindle of the hub, but the external and internalsplines are not engaged; interposing a sleeve on an alignment toolbetween the interior of the hub and the reduced end of the half-shaft toaxially align the external spline on the half-shaft with internal splineof the spindle; advancing the hub/bearing assembly over the half-shaftand toward the body of the universal joint, whereby the spline in thespindle and the spline on the half-shaft engage; and withdrawing thesleeve of the alignment tool from the reduced end portion of thehalf-shaft.
 9. The process according to claim 8 wherein the housing ofthe hub/bearing assembly is attached to a suspension system component.10. The process according to claim 8 wherein the tool has a flange atone end of its sleeve, and when the sleeve is interposed between thereduced end of the half-shaft and interior of the hub, the flange of thetool is located beyond the spline of the hub; and wherein the step ofremoving the tool includes grasping the flange of the tool and pullingthe tool off the reduced end of the half-shaft.
 11. The processaccording to claim 8 wherein the reduced end of the half-shaft has athread, and further comprising engaging a nut with the thread on thereduced end of the half-shaft and tightening the nut against the hub ofthe hub/bearing assembly so that the hub is captured between the nut andthe body of the universal joint.